Diff contact pattern

[Sheepy]

Is there any shims under the pinion bearing? (At the tooth end) if so take off the bearing again and remove another, and retry, unfortunately setting up diff's is a long process,
Shimming, bearing on, testing, bearing off shimming and so on!
And as Marcus says, when you change the pinion, readjust the crown wheel!  :)

I presume that is engineers blue on the teeth (the top two look like blue marker pen)

[GT6 M]

should have siad earlier, there 2 shims to tek oot / put in on pinnion.
one, which I think your on with, which is why ye cant alter contact,  just sets the pree load, the other, which is under the bearing in the diff case.
its  THIS one that ye add or subtrct to get the pinnion into /out of mesh.

the need of some brass drifts is needed, and can easily mek shims oot of shim sheet,
use the bearing outer as a template, scribe aroond, cut oot with scissors, an fit,
mek it smaller than the inner bit of bearing, as if ye nok it back oot, you wont destroy the bit thats sitting under bearing .

SO, add to this bearing, and ye gotta add to small bearing end to keep same pree load
reduce, and e gotta reduce at other end too.

M  

[Martin M]

Hi, the contact is at the very very low end of the tooth, say the lower 25% are only "contracted".
So consensus is that I will reduce shims and thus move pinion away from the CW.
Martin

[GT6 M]

Ermmm yis and no,
If the contact is at the bottom with a high load onit, then Yes, move it up,
If its at bottom with nee load onit, then put a load on fust to see where its at.

If at the bottom where it at noo, then decrease shim {if there is one under the bearing,   IF there aint, ye gotta tek the pinnion bearing off the pinnion head, and reduce there. If deeing it this way, tek moer off than would be for the bearing in the diff, cos its a bit moer of a hand full tek,n the head bearing off }
And decreas by 5 thou, { say 10-12 thou at head bearing, unless yer comfortable tek,n the head bearing off a few times  :o } that should bring it back further up.
READ a few times, so it sinks in. ;)

Must also re doo pree load bt amount ye take off
then gotta adjust CW play too.

BUTTT, must all be checked with a good load on the CW. as the contact pattern alters alott.

M

[GT6 M]

hold on Martin, was talking upside down, arghhh.
it should be, At bottom, Move pinnion into the CW,

At top, move it away

Sorry, got it back to front. hectic morning,  :B

pics  nearly at bottom

http://www.pirate4x4.com/tech/billavista/PR-ARB/articles/14b_Gear_Setup/

M

[Martin M]

should I live with that pattern?
Cheers
Martin

[GT6 M]

If that is wid a lott of load on, then it should be OK,
my self, would have it just a little lower, 3-5 thouh shim
Under load, the tooth pattern rises up the tooth, hence I like it lower.

bigger shime under  bearing in casing, this will mek tooth pattern deeper,
IE to bottom of tooth depth into teeth look OK

Note, ye just cannot get the same patterns on all the teeth, even new,ns are as bad, if not worse.
look closely an ye can see this.

Just touching bottom of tooth with a  4 foot prybar, pulled weel doon, will be just aboout right for you.
{ Ask Chriss, he pulled the darn diff oot the vice, when we check,n His }

Ohhh have ye used brand new bearings !!!
if so, then you gotta put some pree load on em,

I dont no what it is with modern type bearings,  but I had quite a few in that  had new bearings
but the slackness was awfull, seems as thouhg the info for olde bearings, aint what it should be for modern ones..

I tend to set the new,ns slightly tighter, then as they wear / bed in.
they still have a bit of tightness an no slack like most ive took oot.

Change yer oil at least 2 times a year if using it abitt
oil breks doon wid heat, and them wee diff get v v hot

even not many mile, change it every year, stops condensation and rust forming.
as some diff have been internally covered in rust /gunge

M